What Is A Preservative? What Is The Principle Of Anti-corrosion?

  Preservatives are a class of food additives that can inhibit microbial activity and prevent food from spoiling. To make the food have a certain preservation period, certain measures must be adopted to prevent the infection and reproduction of microorganisms. Practice has proved that the use of preservatives is the most economical, effective and simplest way to achieve the above-mentioned purposes.

  Traditionally, the two are often distinguished by use rather than chemical structure, because the same substance, such as phenol, is used as a preservative at low concentrations and as a disinfectant at higher concentrations. Most believe that the term preservative is not suitable for systemic drugs. Drugs commonly used as preservatives and disinfectants include various substitutions of phenol such as biphenols, cresols, xylenols, cationic surface active substances, halogens, and oxidizing agents such as peroxides. Hydrogen (hydrogen per-oxide) and permanganates (perman-ganates), aniline dyes and acridine dyes, heavy metal salts, alcohols (alcohols) and aldehydes (aldehy-des), etc. .

   Preservatives are also used as food additives for the purpose of maintaining the original quality and nutritional value of food. The prescribed preservatives include 25 kinds of benzoic acid, sodium benzoate, sorbic acid, potassium sorbate and calcium propionate.

- The anti-corrosion principles of preservatives are roughly as follows:

1. It interferes with the enzyme system of microorganisms, destroys its normal metabolism and inhibits enzyme activity.

2. It coagulates and denatures the protein of microorganisms and interferes with their survival and reproduction.

3. It changes the permeability of the cell plasma membrane, inhibits the elimination of enzymes and metabolites in the body, and causes its inactivation.